From dbe27a002ef8573168cb64e181458ea23a74e2b6 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Tue, 6 Nov 2018 12:04:54 +0900 Subject: kbuild: add -no-integrated-as Clang option unconditionally We are still a way off the Clang's integrated assembler support for the kernel. Hence, -no-integrated-as is mandatory to build the kernel with Clang. If you had an ancient version of Clang that does not recognize this option, you would not be able to compile the kernel anyway. Signed-off-by: Masahiro Yamada Reviewed-by: Nick Desaulniers Tested-by: Nick Desaulniers --- Makefile | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'Makefile') diff --git a/Makefile b/Makefile index 2f36db897895..b71b9c70496c 100644 --- a/Makefile +++ b/Makefile @@ -497,8 +497,8 @@ CLANG_GCC_TC := --gcc-toolchain=$(GCC_TOOLCHAIN) endif KBUILD_CFLAGS += $(CLANG_TARGET) $(CLANG_GCC_TC) $(CLANG_PREFIX) KBUILD_AFLAGS += $(CLANG_TARGET) $(CLANG_GCC_TC) $(CLANG_PREFIX) -KBUILD_CFLAGS += $(call cc-option, -no-integrated-as) -KBUILD_AFLAGS += $(call cc-option, -no-integrated-as) +KBUILD_CFLAGS += -no-integrated-as +KBUILD_AFLAGS += -no-integrated-as endif RETPOLINE_CFLAGS_GCC := -mindirect-branch=thunk-extern -mindirect-branch-register -- cgit v1.2.3-58-ga151 From 238bcbc4e07fad2fff99c5b157d0c37ccd4d093c Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Tue, 6 Nov 2018 12:04:55 +0900 Subject: kbuild: consolidate Clang compiler flags Collect basic Clang options such as --target, --prefix, --gcc-toolchain, -no-integrated-as into a single variable CLANG_FLAGS so that it can be easily reused in other parts of Makefile. Signed-off-by: Masahiro Yamada Reviewed-by: Nick Desaulniers Tested-by: Nick Desaulniers Acked-by: Greg Hackmann --- Makefile | 13 ++++++------- 1 file changed, 6 insertions(+), 7 deletions(-) (limited to 'Makefile') diff --git a/Makefile b/Makefile index b71b9c70496c..c300ac16c895 100644 --- a/Makefile +++ b/Makefile @@ -487,18 +487,17 @@ endif ifneq ($(shell $(CC) --version 2>&1 | head -n 1 | grep clang),) ifneq ($(CROSS_COMPILE),) -CLANG_TARGET := --target=$(notdir $(CROSS_COMPILE:%-=%)) +CLANG_FLAGS := --target=$(notdir $(CROSS_COMPILE:%-=%)) GCC_TOOLCHAIN_DIR := $(dir $(shell which $(LD))) -CLANG_PREFIX := --prefix=$(GCC_TOOLCHAIN_DIR) +CLANG_FLAGS += --prefix=$(GCC_TOOLCHAIN_DIR) GCC_TOOLCHAIN := $(realpath $(GCC_TOOLCHAIN_DIR)/..) endif ifneq ($(GCC_TOOLCHAIN),) -CLANG_GCC_TC := --gcc-toolchain=$(GCC_TOOLCHAIN) +CLANG_FLAGS += --gcc-toolchain=$(GCC_TOOLCHAIN) endif -KBUILD_CFLAGS += $(CLANG_TARGET) $(CLANG_GCC_TC) $(CLANG_PREFIX) -KBUILD_AFLAGS += $(CLANG_TARGET) $(CLANG_GCC_TC) $(CLANG_PREFIX) -KBUILD_CFLAGS += -no-integrated-as -KBUILD_AFLAGS += -no-integrated-as +CLANG_FLAGS += -no-integrated-as +KBUILD_CFLAGS += $(CLANG_FLAGS) +KBUILD_AFLAGS += $(CLANG_FLAGS) endif RETPOLINE_CFLAGS_GCC := -mindirect-branch=thunk-extern -mindirect-branch-register -- cgit v1.2.3-58-ga151 From 3bd9805090af843b25f97ffe5049f20ade1d86d6 Mon Sep 17 00:00:00 2001 From: Joel Stanley Date: Mon, 12 Nov 2018 14:51:15 +1030 Subject: Makefile: Export clang toolchain variables The powerpc makefile will use these in it's boot wrapper. Signed-off-by: Joel Stanley Signed-off-by: Masahiro Yamada --- Makefile | 1 + 1 file changed, 1 insertion(+) (limited to 'Makefile') diff --git a/Makefile b/Makefile index c300ac16c895..96b4ea5adf91 100644 --- a/Makefile +++ b/Makefile @@ -498,6 +498,7 @@ endif CLANG_FLAGS += -no-integrated-as KBUILD_CFLAGS += $(CLANG_FLAGS) KBUILD_AFLAGS += $(CLANG_FLAGS) +export CLANG_FLAGS endif RETPOLINE_CFLAGS_GCC := -mindirect-branch=thunk-extern -mindirect-branch-register -- cgit v1.2.3-58-ga151 From 0126be38d98815d25d9ec4573541ed4315bf6a88 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Wed, 21 Nov 2018 00:04:18 +0900 Subject: kbuild: announce removal of SUBDIRS if used SUBDIRS has been kept as a backward compatibility since commit ("[PATCH] kbuild: external module support") in 2002. We do not need multiple ways to do the same thing, so I will remove SUBDIRS after the Linux 5.3 release. I cleaned up in-tree code, and updated the document so that nobody would try to use it. Meanwhile, display the following warning if SUBDIRS is used. Makefile:189: ================= WARNING ================ Makefile:190: 'SUBDIRS' will be removed after Linux 5.3 Makefile:191: Please use 'M=' or 'KBUILD_EXTMOD' instead Makefile:192: ========================================== Signed-off-by: Masahiro Yamada Acked-by: Boris Brezillon # for scx200_docflash.c Acked-by: Guenter Roeck # for scx200_wdt.c --- Documentation/kbuild/kbuild.txt | 7 +------ Makefile | 4 ++++ drivers/mtd/maps/scx200_docflash.c | 7 ------- drivers/watchdog/scx200_wdt.c | 7 ------- samples/connector/Makefile | 2 +- 5 files changed, 6 insertions(+), 21 deletions(-) (limited to 'Makefile') diff --git a/Documentation/kbuild/kbuild.txt b/Documentation/kbuild/kbuild.txt index 8390c360d4b3..c9e3d93e7a89 100644 --- a/Documentation/kbuild/kbuild.txt +++ b/Documentation/kbuild/kbuild.txt @@ -81,12 +81,7 @@ KBUILD_EXTMOD -------------------------------------------------- Set the directory to look for the kernel source when building external modules. -The directory can be specified in several ways: -1) Use "M=..." on the command line -2) Environment variable KBUILD_EXTMOD -3) Environment variable SUBDIRS -The possibilities are listed in the order they take precedence. -Using "M=..." will always override the others. +Setting "M=..." takes precedence over KBUILD_EXTMOD. KBUILD_OUTPUT -------------------------------------------------- diff --git a/Makefile b/Makefile index 96b4ea5adf91..9fcd8f81809c 100644 --- a/Makefile +++ b/Makefile @@ -186,6 +186,10 @@ endif # Old syntax make ... SUBDIRS=$PWD is still supported # Setting the environment variable KBUILD_EXTMOD take precedence ifdef SUBDIRS + $(warning ================= WARNING ================) + $(warning 'SUBDIRS' will be removed after Linux 5.3) + $(warning Please use 'M=' or 'KBUILD_EXTMOD' instead) + $(warning ==========================================) KBUILD_EXTMOD ?= $(SUBDIRS) endif diff --git a/drivers/mtd/maps/scx200_docflash.c b/drivers/mtd/maps/scx200_docflash.c index f1c1f737d0d7..7f1a0e690c4f 100644 --- a/drivers/mtd/maps/scx200_docflash.c +++ b/drivers/mtd/maps/scx200_docflash.c @@ -216,10 +216,3 @@ static void __exit cleanup_scx200_docflash(void) module_init(init_scx200_docflash); module_exit(cleanup_scx200_docflash); - -/* - Local variables: - compile-command: "make -k -C ../../.. SUBDIRS=drivers/mtd/maps modules" - c-basic-offset: 8 - End: -*/ diff --git a/drivers/watchdog/scx200_wdt.c b/drivers/watchdog/scx200_wdt.c index 836377cf9271..ec4063ebb41a 100644 --- a/drivers/watchdog/scx200_wdt.c +++ b/drivers/watchdog/scx200_wdt.c @@ -262,10 +262,3 @@ static void __exit scx200_wdt_cleanup(void) module_init(scx200_wdt_init); module_exit(scx200_wdt_cleanup); - -/* - Local variables: - compile-command: "make -k -C ../.. SUBDIRS=drivers/char modules" - c-basic-offset: 8 - End: -*/ diff --git a/samples/connector/Makefile b/samples/connector/Makefile index fe3c8542ae4a..6ad71620e503 100644 --- a/samples/connector/Makefile +++ b/samples/connector/Makefile @@ -14,4 +14,4 @@ HOSTCFLAGS_ucon.o += -I$(objtree)/usr/include all: modules modules clean: - $(MAKE) -C ../.. SUBDIRS=$(CURDIR) $@ + $(MAKE) -C ../.. M=$(CURDIR) $@ -- cgit v1.2.3-58-ga151 From e07db28eea38ed4e332b3a89f3995c86b713cb5b Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Thu, 22 Nov 2018 08:11:54 +0900 Subject: kbuild: fix single target build for external module Building a single target in an external module fails due to missing .tmp_versions directory. For example, $ make -C /lib/modules/$(uname -r)/build M=$PWD foo.o will fail in the following way: CC [M] /home/masahiro/foo/foo.o /bin/sh: 1: cannot create /home/masahiro/foo/.tmp_versions/foo.mod: Directory nonexistent This is because $(cmd_crmodverdir) is executed only before building /, %/, %.ko single targets of external modules. Create .tmp_versions in the 'prepare' target. Signed-off-by: Masahiro Yamada --- Makefile | 11 +++-------- 1 file changed, 3 insertions(+), 8 deletions(-) (limited to 'Makefile') diff --git a/Makefile b/Makefile index 9fcd8f81809c..b2519b9b3599 100644 --- a/Makefile +++ b/Makefile @@ -1551,9 +1551,6 @@ else # KBUILD_EXTMOD # We are always building modules KBUILD_MODULES := 1 -PHONY += crmodverdir -crmodverdir: - $(cmd_crmodverdir) PHONY += $(objtree)/Module.symvers $(objtree)/Module.symvers: @@ -1565,7 +1562,7 @@ $(objtree)/Module.symvers: module-dirs := $(addprefix _module_,$(KBUILD_EXTMOD)) PHONY += $(module-dirs) modules -$(module-dirs): crmodverdir $(objtree)/Module.symvers +$(module-dirs): prepare $(objtree)/Module.symvers $(Q)$(MAKE) $(build)=$(patsubst _module_%,%,$@) modules: $(module-dirs) @@ -1606,7 +1603,8 @@ help: # Dummies... PHONY += prepare scripts -prepare: ; +prepare: + $(cmd_crmodverdir) scripts: ; endif # KBUILD_EXTMOD @@ -1730,17 +1728,14 @@ endif # Modules /: prepare scripts FORCE - $(cmd_crmodverdir) $(Q)$(MAKE) KBUILD_MODULES=$(if $(CONFIG_MODULES),1) \ $(build)=$(build-dir) # Make sure the latest headers are built for Documentation Documentation/ samples/: headers_install %/: prepare scripts FORCE - $(cmd_crmodverdir) $(Q)$(MAKE) KBUILD_MODULES=$(if $(CONFIG_MODULES),1) \ $(build)=$(build-dir) %.ko: prepare scripts FORCE - $(cmd_crmodverdir) $(Q)$(MAKE) KBUILD_MODULES=$(if $(CONFIG_MODULES),1) \ $(build)=$(build-dir) $(@:.ko=.o) $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost -- cgit v1.2.3-58-ga151 From 65bba0423ecf89fb291d2269e0087707888a1cef Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Thu, 29 Nov 2018 11:58:50 +0900 Subject: kbuild: fix UML build error with CONFIG_GCC_PLUGINS UML fails to build with CONFIG_GCC_PLUGINS=y. $ make -s ARCH=um mrproper $ make -s ARCH=um allmodconfig $ make ARCH=um UPD include/generated/uapi/linux/version.h WRAP arch/x86/include/generated/uapi/asm/bpf_perf_event.h WRAP arch/x86/include/generated/uapi/asm/poll.h WRAP arch/x86/include/generated/asm/dma-contiguous.h WRAP arch/x86/include/generated/asm/early_ioremap.h WRAP arch/x86/include/generated/asm/export.h WRAP arch/x86/include/generated/asm/mcs_spinlock.h WRAP arch/x86/include/generated/asm/mm-arch-hooks.h SYSTBL arch/x86/include/generated/asm/syscalls_32.h SYSHDR arch/x86/include/generated/asm/unistd_32_ia32.h SYSHDR arch/x86/include/generated/asm/unistd_64_x32.h SYSTBL arch/x86/include/generated/asm/syscalls_64.h SYSHDR arch/x86/include/generated/uapi/asm/unistd_32.h SYSHDR arch/x86/include/generated/uapi/asm/unistd_64.h SYSHDR arch/x86/include/generated/uapi/asm/unistd_x32.h HOSTCC scripts/unifdef CC arch/x86/um/user-offsets.s cc1: error: cannot load plugin ./scripts/gcc-plugins/cyc_complexity_plugin.so ./scripts/gcc-plugins/cyc_complexity_plugin.so: cannot open shared object file: No such file or directory cc1: error: cannot load plugin ./scripts/gcc-plugins/structleak_plugin.so ./scripts/gcc-plugins/structleak_plugin.so: cannot open shared object file: No such file or directory cc1: error: cannot load plugin ./scripts/gcc-plugins/latent_entropy_plugin.so ./scripts/gcc-plugins/latent_entropy_plugin.so: cannot open shared object file: No such file or directory cc1: error: cannot load plugin ./scripts/gcc-plugins/randomize_layout_plugin.so ./scripts/gcc-plugins/randomize_layout_plugin.so: cannot open shared object file: No such file or directory make[1]: *** [scripts/Makefile.build;119: arch/x86/um/user-offsets.s] Error 1 make: *** [arch/um/Makefile;152: arch/x86/um/user-offsets.s] Error 2 Reorder the preparation stage (with cleanups) to make sure gcc-plugins is built before descending to arch/x86/um/. Fixes: 6b90bd4ba40b ("GCC plugin infrastructure") Reported-by: kbuild test robot Signed-off-by: Masahiro Yamada --- Makefile | 4 ++-- arch/um/Makefile | 24 ++---------------------- arch/x86/um/Makefile | 4 +++- 3 files changed, 7 insertions(+), 25 deletions(-) (limited to 'Makefile') diff --git a/Makefile b/Makefile index b2519b9b3599..bfab340453c6 100644 --- a/Makefile +++ b/Makefile @@ -1110,9 +1110,9 @@ prepare1: prepare2 $(version_h) $(autoksyms_h) include/generated/utsrelease.h macroprepare: prepare1 archmacros -archprepare: archheaders archscripts macroprepare scripts_basic +archprepare: archheaders archscripts macroprepare scripts_basic gcc-plugins -prepare0: archprepare gcc-plugins +prepare0: archprepare $(Q)$(MAKE) $(build)=. # All the preparing.. diff --git a/arch/um/Makefile b/arch/um/Makefile index ab1066c38944..c08035904849 100644 --- a/arch/um/Makefile +++ b/arch/um/Makefile @@ -116,7 +116,8 @@ endef archheaders: $(Q)$(MAKE) -f $(srctree)/Makefile ARCH=$(HEADER_ARCH) asm-generic archheaders -archprepare: include/generated/user_constants.h +archprepare: + $(Q)$(MAKE) $(build)=$(HOST_DIR)/um include/generated/user_constants.h LINK-$(CONFIG_LD_SCRIPT_STATIC) += -static LINK-$(CONFIG_LD_SCRIPT_DYN) += -Wl,-rpath,/lib $(call cc-option, -no-pie) @@ -146,25 +147,4 @@ archclean: @find . \( -name '*.bb' -o -name '*.bbg' -o -name '*.da' \ -o -name '*.gcov' \) -type f -print | xargs rm -f -# Generated files - -$(HOST_DIR)/um/user-offsets.s: __headers FORCE - $(Q)$(MAKE) $(build)=$(HOST_DIR)/um $@ - -define filechk_gen-asm-offsets - (set -e; \ - echo "/*"; \ - echo " * DO NOT MODIFY."; \ - echo " *"; \ - echo " * This file was generated by arch/$(ARCH)/Makefile"; \ - echo " *"; \ - echo " */"; \ - echo ""; \ - sed -ne "/^->/{s:^->\([^ ]*\) [\$$#]*\([^ ]*\) \(.*\):#define \1 \2 /* \3 */:; s:->::; p;}" < $<; \ - echo ""; ) -endef - -include/generated/user_constants.h: $(HOST_DIR)/um/user-offsets.s - $(call filechk,gen-asm-offsets) - export HEADER_ARCH SUBARCH USER_CFLAGS CFLAGS_NO_HARDENING OS DEV_NULL_PATH diff --git a/arch/x86/um/Makefile b/arch/x86/um/Makefile index c2d3d7c51e9e..17924646467c 100644 --- a/arch/x86/um/Makefile +++ b/arch/x86/um/Makefile @@ -36,10 +36,12 @@ subarch-$(CONFIG_MODULES) += ../kernel/module.o USER_OBJS := bugs_$(BITS).o ptrace_user.o fault.o -extra-y += user-offsets.s $(obj)/user-offsets.s: c_flags = -Wp,-MD,$(depfile) $(USER_CFLAGS) \ -Iarch/x86/include/generated +include/generated/user_constants.h: $(obj)/user-offsets.s + $(call filechk,offsets,__USER_CONSTANT_H__) + UNPROFILE_OBJS := stub_segv.o CFLAGS_stub_segv.o := $(CFLAGS_NO_HARDENING) -- cgit v1.2.3-58-ga151 From 60df1aee2aecb53efb4218b4dfdf7d6c80a5a3de Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Thu, 29 Nov 2018 12:13:24 +0900 Subject: kbuild: move modpost out of 'scripts' target I am eagar to build under the scripts/ directory only with $(HOSTCC), but scripts/mod/ highly depends on the $(CC) and target arch headers. That it why the 'scripts' target must depend on 'asm-generic', 'gcc-plugins', and $(autoksyms_h). Move it to the 'prepare0' stage. I know this is a cheesy workaround, but better than the current situation. Signed-off-by: Masahiro Yamada --- Makefile | 3 ++- scripts/Makefile | 3 +-- scripts/mod/Makefile | 2 -- 3 files changed, 3 insertions(+), 5 deletions(-) (limited to 'Makefile') diff --git a/Makefile b/Makefile index bfab340453c6..6da46310a662 100644 --- a/Makefile +++ b/Makefile @@ -1075,7 +1075,7 @@ include/config/kernel.release: $(srctree)/Makefile FORCE # Carefully list dependencies so we do not try to build scripts twice # in parallel PHONY += scripts -scripts: scripts_basic scripts_dtc asm-generic gcc-plugins $(autoksyms_h) +scripts: scripts_basic scripts_dtc $(Q)$(MAKE) $(build)=$(@) # Things we need to do before we recursively start building the kernel @@ -1113,6 +1113,7 @@ macroprepare: prepare1 archmacros archprepare: archheaders archscripts macroprepare scripts_basic gcc-plugins prepare0: archprepare + $(Q)$(MAKE) $(build)=scripts/mod $(Q)$(MAKE) $(build)=. # All the preparing.. diff --git a/scripts/Makefile b/scripts/Makefile index ece52ff20171..b48259d30280 100644 --- a/scripts/Makefile +++ b/scripts/Makefile @@ -37,9 +37,8 @@ build_unifdef: $(obj)/unifdef @: subdir-$(CONFIG_MODVERSIONS) += genksyms -subdir-y += mod subdir-$(CONFIG_SECURITY_SELINUX) += selinux subdir-$(CONFIG_GDB_SCRIPTS) += gdb # Let clean descend into subdirs -subdir- += basic dtc kconfig package gcc-plugins +subdir- += basic dtc kconfig mod package gcc-plugins diff --git a/scripts/mod/Makefile b/scripts/mod/Makefile index a5b4af47987a..42c5d50f2bcc 100644 --- a/scripts/mod/Makefile +++ b/scripts/mod/Makefile @@ -4,8 +4,6 @@ OBJECT_FILES_NON_STANDARD := y hostprogs-y := modpost mk_elfconfig always := $(hostprogs-y) empty.o -CFLAGS_REMOVE_empty.o := $(ASM_MACRO_FLAGS) - modpost-objs := modpost.o file2alias.o sumversion.o devicetable-offsets-file := devicetable-offsets.h -- cgit v1.2.3-58-ga151 From 059bc9fc375e00f159f9d7c5ca9d18ab843f95de Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Thu, 29 Nov 2018 12:56:30 +0900 Subject: kbuild: make 'archprepare' depend on 'scripts' Before start descending, Kbuild needs to run 'prepare' and 'scripts', which has been orthogonal to each other. Going forward, let's consider 'scripts' is a part of the preparation. This will allow more cleanups. Move 'scripts' to the prerequisite of 'archprepare', where UML starts compiling target *.c files. Signed-off-by: Masahiro Yamada --- Makefile | 32 +++++++++++++++----------------- 1 file changed, 15 insertions(+), 17 deletions(-) (limited to 'Makefile') diff --git a/Makefile b/Makefile index 6da46310a662..06b6424d519a 100644 --- a/Makefile +++ b/Makefile @@ -1060,7 +1060,7 @@ $(sort $(vmlinux-deps)): $(vmlinux-dirs) ; # Error messages still appears in the original language PHONY += $(vmlinux-dirs) -$(vmlinux-dirs): prepare scripts +$(vmlinux-dirs): prepare $(Q)$(MAKE) $(build)=$@ need-builtin=1 define filechk_kernel.release @@ -1110,7 +1110,7 @@ prepare1: prepare2 $(version_h) $(autoksyms_h) include/generated/utsrelease.h macroprepare: prepare1 archmacros -archprepare: archheaders archscripts macroprepare scripts_basic gcc-plugins +archprepare: archheaders archscripts macroprepare scripts gcc-plugins prepare0: archprepare $(Q)$(MAKE) $(build)=scripts/mod @@ -1284,7 +1284,7 @@ modules.builtin: $(vmlinux-dirs:%=%/modules.builtin) # Target to prepare building external modules PHONY += modules_prepare -modules_prepare: prepare scripts +modules_prepare: prepare # Target to install modules PHONY += modules_install @@ -1602,11 +1602,9 @@ help: @echo ' clean - remove generated files in module directory only' @echo '' -# Dummies... -PHONY += prepare scripts +PHONY += prepare prepare: $(cmd_crmodverdir) -scripts: ; endif # KBUILD_EXTMOD clean: $(clean-dirs) @@ -1710,33 +1708,33 @@ else target-dir = $(if $(KBUILD_EXTMOD),$(dir $<),$(dir $@)) endif -%.s: %.c prepare scripts FORCE +%.s: %.c prepare FORCE $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@) -%.i: %.c prepare scripts FORCE +%.i: %.c prepare FORCE $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@) -%.o: %.c prepare scripts FORCE +%.o: %.c prepare FORCE $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@) -%.lst: %.c prepare scripts FORCE +%.lst: %.c prepare FORCE $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@) -%.s: %.S prepare scripts FORCE +%.s: %.S prepare FORCE $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@) -%.o: %.S prepare scripts FORCE +%.o: %.S prepare FORCE $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@) -%.symtypes: %.c prepare scripts FORCE +%.symtypes: %.c prepare FORCE $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@) -%.ll: %.c prepare scripts FORCE +%.ll: %.c prepare FORCE $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@) # Modules -/: prepare scripts FORCE +/: prepare FORCE $(Q)$(MAKE) KBUILD_MODULES=$(if $(CONFIG_MODULES),1) \ $(build)=$(build-dir) # Make sure the latest headers are built for Documentation Documentation/ samples/: headers_install -%/: prepare scripts FORCE +%/: prepare FORCE $(Q)$(MAKE) KBUILD_MODULES=$(if $(CONFIG_MODULES),1) \ $(build)=$(build-dir) -%.ko: prepare scripts FORCE +%.ko: prepare FORCE $(Q)$(MAKE) KBUILD_MODULES=$(if $(CONFIG_MODULES),1) \ $(build)=$(build-dir) $(@:.ko=.o) $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost -- cgit v1.2.3-58-ga151 From ce2fd53a10c7d17934c005029382f8310e565504 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Thu, 29 Nov 2018 12:56:31 +0900 Subject: kbuild: descend into scripts/gcc-plugins/ via scripts/Makefile Now that 'archprepare' depends on 'scripts', Kbuild can descend into scripts/gcc-plugins in a more standard way. Signed-off-by: Masahiro Yamada Reviewed-by: Kees Cook --- Makefile | 2 +- scripts/Makefile | 3 ++- scripts/Makefile.gcc-plugins | 8 -------- 3 files changed, 3 insertions(+), 10 deletions(-) (limited to 'Makefile') diff --git a/Makefile b/Makefile index 06b6424d519a..861d9d48c7df 100644 --- a/Makefile +++ b/Makefile @@ -1110,7 +1110,7 @@ prepare1: prepare2 $(version_h) $(autoksyms_h) include/generated/utsrelease.h macroprepare: prepare1 archmacros -archprepare: archheaders archscripts macroprepare scripts gcc-plugins +archprepare: archheaders archscripts macroprepare scripts prepare0: archprepare $(Q)$(MAKE) $(build)=scripts/mod diff --git a/scripts/Makefile b/scripts/Makefile index b48259d30280..feb1f71381d7 100644 --- a/scripts/Makefile +++ b/scripts/Makefile @@ -36,9 +36,10 @@ PHONY += build_unifdef build_unifdef: $(obj)/unifdef @: +subdir-$(CONFIG_GCC_PLUGINS) += gcc-plugins subdir-$(CONFIG_MODVERSIONS) += genksyms subdir-$(CONFIG_SECURITY_SELINUX) += selinux subdir-$(CONFIG_GDB_SCRIPTS) += gdb # Let clean descend into subdirs -subdir- += basic dtc kconfig mod package gcc-plugins +subdir- += basic dtc kconfig mod package diff --git a/scripts/Makefile.gcc-plugins b/scripts/Makefile.gcc-plugins index 46c5c6809806..c36f19959619 100644 --- a/scripts/Makefile.gcc-plugins +++ b/scripts/Makefile.gcc-plugins @@ -49,11 +49,3 @@ KBUILD_CFLAGS += $(GCC_PLUGINS_CFLAGS) # All enabled GCC plugins are collected here for building below. GCC_PLUGIN := $(gcc-plugin-y) export GCC_PLUGIN - -# Actually do the build, if requested. -PHONY += gcc-plugins -gcc-plugins: scripts_basic -ifdef CONFIG_GCC_PLUGINS - $(Q)$(MAKE) $(build)=scripts/gcc-plugins -endif - @: -- cgit v1.2.3-58-ga151 From 392885ee82d35d515ba2af7b72c5e357c3002113 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Fri, 30 Nov 2018 10:05:22 +0900 Subject: kbuild: let fixdep directly write to .*.cmd files Currently, fixdep writes dependencies to .*.tmp, which is renamed to .*.cmd after everything succeeds. This is a very safe way to avoid corrupted .*.cmd files. The if_changed_dep has carried this safety mechanism since it was added in 2002. If fixdep fails for some reasons or a user terminates the build while fixdep is running, the incomplete output from the fixdep could be troublesome. This is my insight about some bad scenarios: [1] If the compiler succeeds to generate *.o file, but fixdep fails to write necessary dependencies to .*.cmd file, Make will miss to rebuild the object when headers or CONFIG options are changed. In this case, fixdep should not generate .*.cmd file at all so that 'arg-check' will surely trigger the rebuild of the object. [2] A partially constructed .*.cmd file may not be a syntactically correct makefile. The next time Make runs, it would include it, then fail to parse it. Once this happens, 'make clean' is be the only way to fix it. In fact, [1] is no longer a problem since commit 9c2af1c7377a ("kbuild: add .DELETE_ON_ERROR special target"). Make deletes a target file on any failure in its recipe. Because fixdep is a part of the recipe of *.o target, if it fails, the *.o is deleted anyway. However, I am a bit worried about the slight possibility of [2]. So, here is a solution. Let fixdep directly write to a .*.cmd file, but allow makefiles to include it only when its corresponding target exists. This effectively reverts commit 2982c953570b ("kbuild: remove redundant $(wildcard ...) for cmd_files calculation"), and commit 00d78ab2ba75 ("kbuild: remove dead code in cmd_files calculation in top Makefile") because now we must check the presence of targets. Signed-off-by: Masahiro Yamada --- Makefile | 13 +++++++------ scripts/Kbuild.include | 10 ++++------ scripts/Makefile.build | 12 +++++------- 3 files changed, 16 insertions(+), 19 deletions(-) (limited to 'Makefile') diff --git a/Makefile b/Makefile index 861d9d48c7df..d4ac3cb9256c 100644 --- a/Makefile +++ b/Makefile @@ -1043,6 +1043,8 @@ ifdef CONFIG_GDB_SCRIPTS endif +$(call if_changed,link-vmlinux) +targets := vmlinux + # Build samples along the rest of the kernel. This needs headers_install. ifdef CONFIG_SAMPLES vmlinux-dirs += samples @@ -1758,13 +1760,12 @@ quiet_cmd_depmod = DEPMOD $(KERNELRELEASE) cmd_crmodverdir = $(Q)mkdir -p $(MODVERDIR) \ $(if $(KBUILD_MODULES),; rm -f $(MODVERDIR)/*) -# read all saved command lines -cmd_files := $(wildcard .*.cmd) +# read saved command lines for existing targets +existing-targets := $(wildcard $(sort $(targets))) -ifneq ($(cmd_files),) - $(cmd_files): ; # Do not try to update included dependency files - include $(cmd_files) -endif +cmd_files := $(foreach f,$(existing-targets),$(dir $(f)).$(notdir $(f)).cmd) +$(cmd_files): ; # Do not try to update included dependency files +-include $(cmd_files) endif # ifeq ($(config-targets),1) endif # ifeq ($(mixed-targets),1) diff --git a/scripts/Kbuild.include b/scripts/Kbuild.include index bb015551c2d9..6cf6a8b83b97 100644 --- a/scripts/Kbuild.include +++ b/scripts/Kbuild.include @@ -264,9 +264,8 @@ ifndef CONFIG_TRIM_UNUSED_KSYMS cmd_and_fixdep = \ $(echo-cmd) $(cmd_$(1)); \ - scripts/basic/fixdep $(depfile) $@ '$(make-cmd)' > $(dot-target).tmp;\ - rm -f $(depfile); \ - mv -f $(dot-target).tmp $(dot-target).cmd; + scripts/basic/fixdep $(depfile) $@ '$(make-cmd)' > $(dot-target).cmd;\ + rm -f $(depfile); else @@ -289,9 +288,8 @@ cmd_and_fixdep = \ $(echo-cmd) $(cmd_$(1)); \ $(ksym_dep_filter) | \ scripts/basic/fixdep -e $(depfile) $@ '$(make-cmd)' \ - > $(dot-target).tmp; \ - rm -f $(depfile); \ - mv -f $(dot-target).tmp $(dot-target).cmd; + > $(dot-target).cmd; \ + rm -f $(depfile); endif diff --git a/scripts/Makefile.build b/scripts/Makefile.build index a8e7ba9f73e8..6835f98e2070 100644 --- a/scripts/Makefile.build +++ b/scripts/Makefile.build @@ -529,18 +529,16 @@ FORCE: # optimization, we don't need to read them if the target does not # exist, we will rebuild anyway in that case. -cmd_files := $(wildcard $(foreach f,$(sort $(targets)),$(dir $(f)).$(notdir $(f)).cmd)) +existing-targets := $(wildcard $(sort $(targets))) -ifneq ($(cmd_files),) - include $(cmd_files) -endif +-include $(foreach f,$(existing-targets),$(dir $(f)).$(notdir $(f)).cmd) ifneq ($(KBUILD_SRC),) # Create directories for object files if they do not exist obj-dirs := $(sort $(obj) $(patsubst %/,%, $(dir $(targets)))) -# If cmd_files exist, their directories apparently exist. Skip mkdir. -exist-dirs := $(sort $(patsubst %/,%, $(dir $(cmd_files)))) -obj-dirs := $(strip $(filter-out $(exist-dirs), $(obj-dirs))) +# If targets exist, their directories apparently exist. Skip mkdir. +existing-dirs := $(sort $(patsubst %/,%, $(dir $(existing-targets)))) +obj-dirs := $(strip $(filter-out $(existing-dirs), $(obj-dirs))) ifneq ($(obj-dirs),) $(shell mkdir -p $(obj-dirs)) endif -- cgit v1.2.3-58-ga151 From 257edce66d31a345dff8ca9f1fd30c46e0f14058 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Wed, 5 Dec 2018 16:38:35 +0900 Subject: kbuild: exploit parallel building for CONFIG_HEADERS_CHECK When CONFIG_HEADERS_CHECK is enabled, the headers_check is executed as a serialized task in the vmlinux recipe. Make it independent of vmlinux so that parallel building can process the headers_check and other build targets simultaneously. Signed-off-by: Masahiro Yamada --- Makefile | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) (limited to 'Makefile') diff --git a/Makefile b/Makefile index d4ac3cb9256c..00630cf04d84 100644 --- a/Makefile +++ b/Makefile @@ -1035,9 +1035,6 @@ cmd_link-vmlinux = \ $(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) $@, true) vmlinux: scripts/link-vmlinux.sh autoksyms_recursive $(vmlinux-deps) FORCE -ifdef CONFIG_HEADERS_CHECK - $(Q)$(MAKE) -f $(srctree)/Makefile headers_check -endif ifdef CONFIG_GDB_SCRIPTS $(Q)ln -fsn $(abspath $(srctree)/scripts/gdb/vmlinux-gdb.py) endif @@ -1208,6 +1205,10 @@ headers_check: headers_install $(Q)$(MAKE) $(hdr-inst)=include/uapi dst=include HDRCHECK=1 $(Q)$(MAKE) $(hdr-inst)=arch/$(SRCARCH)/include/uapi $(hdr-dst) HDRCHECK=1 +ifdef CONFIG_HEADERS_CHECK +all: headers_check +endif + # --------------------------------------------------------------------------- # Kernel selftest -- cgit v1.2.3-58-ga151 From 7d0e5c2056c70ff443188b6e603b6254af1304cc Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Wed, 5 Dec 2018 20:28:04 +0900 Subject: kbuild: refactor Makefile.asm-generic - Use conventional $(MAKE) $(asm-generic)= style for directory descending - Remove unneeded FORCE since "all" is a phony target - Remove unneeded "_dummy :=" assignment - Skip $(shell mkdir ...) when headers exist in the directory - Misc cleanups Signed-off-by: Masahiro Yamada Acked-by: Sam Ravnborg --- Makefile | 8 ++++---- scripts/Makefile.asm-generic | 37 +++++++++++++++++++------------------ 2 files changed, 23 insertions(+), 22 deletions(-) (limited to 'Makefile') diff --git a/Makefile b/Makefile index 00630cf04d84..6f3df2d786dd 100644 --- a/Makefile +++ b/Makefile @@ -1119,13 +1119,13 @@ prepare0: archprepare prepare: prepare0 prepare-objtool # Support for using generic headers in asm-generic +asm-generic := -f $(srctree)/scripts/Makefile.asm-generic obj + PHONY += asm-generic uapi-asm-generic asm-generic: uapi-asm-generic - $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.asm-generic \ - src=asm obj=arch/$(SRCARCH)/include/generated/asm + $(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/asm uapi-asm-generic: - $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.asm-generic \ - src=uapi/asm obj=arch/$(SRCARCH)/include/generated/uapi/asm + $(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/uapi/asm PHONY += prepare-objtool prepare-objtool: $(objtool_target) diff --git a/scripts/Makefile.asm-generic b/scripts/Makefile.asm-generic index 32ad8e93fbe1..760323e70ebc 100644 --- a/scripts/Makefile.asm-generic +++ b/scripts/Makefile.asm-generic @@ -2,41 +2,42 @@ # include/asm-generic contains a lot of files that are used # verbatim by several architectures. # -# This Makefile reads the file arch/$(SRCARCH)/include/$(src)/Kbuild +# This Makefile reads the file arch/$(SRCARCH)/include/(uapi/)/asm/Kbuild # and for each file listed in this file with generic-y creates -# a small wrapper file in $(obj) (arch/$(SRCARCH)/include/generated/$(src)) +# a small wrapper file in arch/$(SRCARCH)/include/generated/(uapi/)/asm. PHONY := all all: -kbuild-file := $(srctree)/arch/$(SRCARCH)/include/$(src)/Kbuild --include $(kbuild-file) +src := $(subst /generated,,$(obj)) +-include $(src)/Kbuild include scripts/Kbuild.include -# Create output directory if not already present -_dummy := $(shell [ -d $(obj) ] || mkdir -p $(obj)) +generic-y := $(addprefix $(obj)/, $(generic-y)) +generated-y := $(addprefix $(obj)/, $(generated-y)) -# Stale wrappers when the corresponding files are removed from generic-y -# need removing. -generated-y := $(generic-y) $(generated-y) -all-files := $(patsubst %, $(obj)/%, $(generated-y)) -old-headers := $(wildcard $(obj)/*.h) -unwanted := $(filter-out $(all-files),$(old-headers)) +# Remove stale wrappers when the corresponding files are removed from generic-y +old-headers := $(wildcard $(obj)/*.h) +unwanted := $(filter-out $(generic-y) $(generated-y),$(old-headers)) quiet_cmd_wrap = WRAP $@ -cmd_wrap = echo "\#include " >$@ + cmd_wrap = echo "\#include " > $@ quiet_cmd_remove = REMOVE $(unwanted) -cmd_remove = rm -f $(unwanted) + cmd_remove = rm -f $(unwanted) -all: $(patsubst %, $(obj)/%, $(generic-y)) FORCE - $(if $(unwanted),$(call cmd,remove),) +all: $(generic-y) + $(if $(unwanted),$(call cmd,remove)) @: $(obj)/%.h: $(call cmd,wrap) -PHONY += FORCE +# Create output directory. Skip it if at least one old header exists +# since we know the output directory already exists. +ifeq ($(old-headers),) +$(shell mkdir -p $(obj)) +endif + .PHONY: $(PHONY) -FORCE: ; -- cgit v1.2.3-58-ga151 From 42a92bccd213ce4b7198d2e943ac0efe88cbe1aa Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Fri, 14 Dec 2018 17:05:37 +0900 Subject: kbuild: add -fno-PIE flag unconditionally This flag is documented in the GCC 4.6 manual, and recognized by Clang as well. Let's rip off the cc-option switch. Signed-off-by: Masahiro Yamada Reviewed-by: Nick Desaulniers --- Makefile | 7 ++----- 1 file changed, 2 insertions(+), 5 deletions(-) (limited to 'Makefile') diff --git a/Makefile b/Makefile index 6f3df2d786dd..2d15726fb546 100644 --- a/Makefile +++ b/Makefile @@ -426,9 +426,9 @@ LINUXINCLUDE := \ -I$(objtree)/include \ $(USERINCLUDE) -KBUILD_AFLAGS := -D__ASSEMBLY__ +KBUILD_AFLAGS := -D__ASSEMBLY__ -fno-PIE KBUILD_CFLAGS := -Wall -Wundef -Wstrict-prototypes -Wno-trigraphs \ - -fno-strict-aliasing -fno-common -fshort-wchar \ + -fno-strict-aliasing -fno-common -fshort-wchar -fno-PIE \ -Werror-implicit-function-declaration \ -Wno-format-security \ -std=gnu89 @@ -514,9 +514,6 @@ RETPOLINE_VDSO_CFLAGS := $(call cc-option,$(RETPOLINE_VDSO_CFLAGS_GCC),$(call cc export RETPOLINE_CFLAGS export RETPOLINE_VDSO_CFLAGS -KBUILD_CFLAGS += $(call cc-option,-fno-PIE) -KBUILD_AFLAGS += $(call cc-option,-fno-PIE) - # check for 'asm goto' ifeq ($(shell $(CONFIG_SHELL) $(srctree)/scripts/gcc-goto.sh $(CC) $(KBUILD_CFLAGS)), y) CC_HAVE_ASM_GOTO := 1 -- cgit v1.2.3-58-ga151 From eeb5687a7139649e1724674441580b778f5ff7ab Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Fri, 14 Dec 2018 17:05:38 +0900 Subject: kbuild: add -Werror=strict-prototypes flag unconditionally -Wstrict-prototypes is added to KBUILD_CFLAGS first, then overridden by -Werror=strict-prototypes later. Let's add -Werror=strict-prototypes unconditionally because it is supported by GCC 4.6, and also by Clang. Signed-off-by: Masahiro Yamada Reviewed-by: Nick Desaulniers --- Makefile | 5 +---- 1 file changed, 1 insertion(+), 4 deletions(-) (limited to 'Makefile') diff --git a/Makefile b/Makefile index 2d15726fb546..1ec5289a871f 100644 --- a/Makefile +++ b/Makefile @@ -427,7 +427,7 @@ LINUXINCLUDE := \ $(USERINCLUDE) KBUILD_AFLAGS := -D__ASSEMBLY__ -fno-PIE -KBUILD_CFLAGS := -Wall -Wundef -Wstrict-prototypes -Wno-trigraphs \ +KBUILD_CFLAGS := -Wall -Wundef -Werror=strict-prototypes -Wno-trigraphs \ -fno-strict-aliasing -fno-common -fshort-wchar -fno-PIE \ -Werror-implicit-function-declaration \ -Wno-format-security \ @@ -832,9 +832,6 @@ KBUILD_CFLAGS += $(call cc-option,-fconserve-stack) # disallow errors like 'EXPORT_GPL(foo);' with missing header KBUILD_CFLAGS += $(call cc-option,-Werror=implicit-int) -# require functions to have arguments in prototypes, not empty 'int foo()' -KBUILD_CFLAGS += $(call cc-option,-Werror=strict-prototypes) - # Prohibit date/time macros, which would make the build non-deterministic KBUILD_CFLAGS += $(call cc-option,-Werror=date-time) -- cgit v1.2.3-58-ga151 From 61a0902a06d602377cb6526deacfe4f0a7eade73 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Fri, 14 Dec 2018 17:05:39 +0900 Subject: kbuild: add -Werror=implicit-int flag unconditionally This flag is documented in the GCC 4.6 manual, and recognized by Clang as well. Let's rip off the cc-option switch. Signed-off-by: Masahiro Yamada Reviewed-by: Nick Desaulniers --- Makefile | 5 +---- 1 file changed, 1 insertion(+), 4 deletions(-) (limited to 'Makefile') diff --git a/Makefile b/Makefile index 1ec5289a871f..b9e902e8e382 100644 --- a/Makefile +++ b/Makefile @@ -429,7 +429,7 @@ LINUXINCLUDE := \ KBUILD_AFLAGS := -D__ASSEMBLY__ -fno-PIE KBUILD_CFLAGS := -Wall -Wundef -Werror=strict-prototypes -Wno-trigraphs \ -fno-strict-aliasing -fno-common -fshort-wchar -fno-PIE \ - -Werror-implicit-function-declaration \ + -Werror-implicit-function-declaration -Werror=implicit-int \ -Wno-format-security \ -std=gnu89 KBUILD_CPPFLAGS := -D__KERNEL__ @@ -829,9 +829,6 @@ KBUILD_CFLAGS += $(call cc-option,-fno-stack-check,) # conserve stack if available KBUILD_CFLAGS += $(call cc-option,-fconserve-stack) -# disallow errors like 'EXPORT_GPL(foo);' with missing header -KBUILD_CFLAGS += $(call cc-option,-Werror=implicit-int) - # Prohibit date/time macros, which would make the build non-deterministic KBUILD_CFLAGS += $(call cc-option,-Werror=date-time) -- cgit v1.2.3-58-ga151